code: def test_functionality_proxy():
      """Test GL proxy class for full functionality."""
      # By using debug mode, we are using the proxy class
      _test_functionality("gl2 debug")
  
file_path: vispy/vispy/gloo/gl/tests/test_functionality.py
imports: import sys
  import numpy
  from vispy.app import Canvas
  from vispy.testing import requires_application, requires_pyopengl, SkipTest, run_tests_if_main, assert_equal, assert_true
  from vispy.gloo import gl
  import pytest
label_desc: Use image node_id 3 for calling a global function with example usage: test_functionality_proxy() without return types